Abstract The proposed project will utilize the comprehensive datasets from the Comparison of Age-related Macular Degeneration (AMD) Treatments Trials (CATT) and CATT Follow-up Study (CATT FS), both sponsored by the National Eye Institute, to address the following important aims: Aim #1: To develop an early treatment response score that is based on vision response and OCT morphological responses in the first 3 months and to evaluate the score's ability to predict long-term vision outcome. Aim #2: To evaluate the cross-sectional association of exploratory OCT features with visual acuity and to determine their ability to predict long-term vision outcome. Aim #3: To assess the progression of non-geographic atrophy to geographic atrophy and the risk factors for its progression during anti-VEGF treatment. Aim #4: To determine associations of medication use with incidence and growth of geographic atrophy during anti-VEGF treatment. The specific aims of this proposal do not include the goals of CATT and CATT FS as the main result papers and many secondary papers from CATT have been published (total of 41 publications). There is also no overlap with the previously successfully completed R21 for the secondary analysis of CATT data (total of 15 publications). The datasets from CATT and CATT FS are unique resources to develop an early treatment response score for predicting the long-term vision outcome, and to evaluate the association of medication use with incidence and growth of geographic atrophy, the leading cause of vision loss in eyes treated with anti-VEGF for neovascular AMD (nAMD). Completion of Aims #1 and #2 will provide a clinically useful tool for predicting the long-term vision outcome to optimize the treatment outcome of the nAMD, and provide a surrogate outcome measure for clinical trials of nAMD. Completion of Aims #3 and #4 may help identify effective strategies for preventing or treating the geographic atrophy. This study will lead to the best clinical care of patients with nAMD, and eventually reduce the risk of vision loss from nAMD. The very large sample size, high quality of datasets, as well as the rich experience and high productivity of the CATT investigators, support the feasibility and likelihood of high yield of the proposed project.